The most recent big twist we've seen are Mega evolutions. Special temporary evolutions that allow Pokémon who have (supposedly) reached the final stage in their evolutionary line, to surpass this limit and become even stronger, with the magical power of friendship or whatever~
(along with Primal Reversion, which is technically Mega evolution with a different prefix and a different "trigger/backstory") And no doubt, we will see more of these in the future.
But could there be another "evolution" concept which would catch everyone by surprise if implemented?
Well...remember the mascot of the franchise? Everyones favourite and/or most disliked Pokémon, Pikachu. What I'm getting at, is that there is one further group of Pokémon that Gamefreak might throw into the spotlight sometime in the future: NFE-Pokemon (not fully evolved).
It could very well be the case, that more fans consider some NFE Pokémon as their favourite, than one would expect.
Let's say a new evolution-twist was to be added, specifically to include (but not necessarily be limited to) NFE-Pokémon, it would then logically follow that these Pokémon would keep the design mostly identical (since the look is the whole point of keeping a Pokémon forever unevolved in the first place).
- stronger (say anywhere from +80 to +180 added to their base stats depending on the Pokémon)
- while retaining most of its familiar look (some interesting detail "added", perhaps a colour altered)
- gain a unique and fitting prefix
- get the chance to learn a new signature move
- in some cases have its type changed
- in some cases gaining a different ability.
Continuing my example, a Dragonair could then pseudo-evolve (no idea what the process would actually be called) to... let's call it a "Majestic Dragonair", have the horn become a crown-like detail instead, its colouration become more intense, its stats increase from
learn a unique new Dragon-type variation of "Quiver Dance" at Lv.55, and perhaps even become a Dragon/Water type.
The evolution would be permanent and it would never be able to evolve into a Dragonite.
But wait a second... what if they are already implementing this right now? (by now, especially for anyone who is aware of things hackers have found in XY a long time ago, it's obvious what I'll bring up)
Eternal Floette. Also known as AZs Floette, it is a special form of Floette that holds a drastically different flower. We have met it already in the final part of the main-story in XY, as AZs very old Partner-Pokémon.
From datamining, we also know that it is actually programmed into the games as a real Pokémon, and that unlike regular Floette, it has stats as high as a Florges (without being able to evolve into Florges) but distributed quite differently from it. It is also capable of learning a new move called "Light of Ruin" (which is like a special Fairy-type Volt-Tackle) which Florges also cannot learn...and so far there has been no way to actually obtain it.
So it might not be THAT unrealistic if sooner or later, we see a special stronger pseudo-evolution for all kinds of Pokémon like in this group-picture:
And of course the aforementioned Pikachu (if the design is done right, even the one in the Anime could finally cash-in on such a new twist, since it would still be a Pikachu, rather than becoming something else entirely).
While NFE Pokémon could be the focus, it would also be an opportunity for some fully-evolved ones to become a lot more viable than a simple Mega evolution would allow (since stat increase isn't fixed to +100), while at the same time not alienating its fans (since the core design stays the same), but no regular evolutions are in sight, like some examples included in the picture above.